9911796707
TMI Blog2002 (8) TMI 367X X X X Extracts X X X X X X X X Extracts X X X X ..... venue seeks for classification of the item under residuary heading other under sub-heading 8479.89 of the Customs Tariff Act. The machine uses the technology of the ultrasonic sound for the purpose of washing ball bearings. It consists of demagnetzing unit, ultrasonic chamber and jet cleaning system, the essential elements of this being the Generator or Power supply Transducer, Processing tank. As per the technical details, which were placed before the Commissioner, it was seen that the items Ultrasonic cleaning is the latest technology adopted for the bearing cleaning all over the world, as the removal of foreign particles by forced cleaning/brush clearing cannot reach inside the component and still some amount of dirt particles will be ..... X X X X Extracts X X X X X X X X Extracts X X X X ..... about 5 to 10 microns. This is done with the aid of superfinishing/honing stones/sticks which are made of fine abrasives formed as stones with bonding material. The iron particles will stick with the components and then due to the abrasion involved in the surfaces becomes dust and paste is also formed. This cannot be normally removed, until a forced cleaning like brush cleaning or ultrasonic cleaning is done. If these foreign particles are not removed from the rings, the dirt particles will distrupt the lubricating produce noise. Solid foreign particles lead to running noise, wear and premature failure. Hard particles in rolling bearings cause abrasive wear, particularly in contact areas with a high rate of sliding friction. Wear even ..... X X X X Extracts X X X X X X X X Extracts X X X X ..... outer rings are made free of foreign particles, then the process of demagnetizing takes places. Thereafter the process of ultrasonic cleaning is done besides the jet washing and thoroughly cleaned inner and outer rings. This is carried out for the following three purposes :- (1) As preparation for a process such as plating, painting or bonding. (2) When a high degree of cleanliness is essential to make the article attractive. (3) When contaminants must be removed to prevent subsequent malfunction or undue wear. 3. The function of each of the item which is there in the ultrasonic cleaning system viz. (a) generator or power supply (b) transducer (c) processing tank has been brought out in the write up which is noted herein ..... X X X X Extracts X X X X X X X X Extracts X X X X ..... y of fresh cleaning liquid to the surface of the article being cleaned. Degassing : Most liquids contain dissolved or entrapped gas. To achieve efficient Ultrasonic Cleaning. Cavitation : A wave usually travels with rarefactions and compressions. When the Ultrasonic wave travels through the liquid it causes rarefactions and compressions in the liquid 22000/40000 times a second. This causes formation of bubbles during the rarefaction phase and collapsing of the bubbles during the compression phase of the ultrasonic wave. This process of formation and collapsing of the bubbles is known as cavitation. From theoretical calculations it has been estimated that a pressure of more than 350 NM/m2 and a temperature greater than 5500 C is create ..... X X X X Extracts X X X X X X X X Extracts X X X X
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